PURPOSE: To decrease noise and to improve S/N by forming an intra-surface magnetized layer which is a lower layer of a perpendicular magnetic recording medium having two-layred structure to the coercive force larger than heretofore.
CONSTITUTION: The intro-surface magnetized layer 2 is provided to the lower layer of the perpendicular magnetic recording medium having the two-layered structure. The coercive force of the layer 2, which is heretofore ≤5 (Oe), is specified to the consideably increased range; i.e., 50W300 (Oe) and the coercive force of the perpendicularly magnetized layer 3 is set within the prescribed range corresponding thereto, by which the fluctuation in the magnetic moment is decreased and the generation of magnetic walls is eventually suppressed. The S/N at the time of reproduction is thereby improved.
HIRONO SHIGERU
OTANI YOSHIMITSU
TERADA AKIRA
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